In the past, a distributed storage in which data is stored by using servers has been known. In addition, in the distributed storage, there is known a technology in which data is duplicated and stored in servers, thereby avoiding a loss of data caused by a failure of a server. As a related technology, there is known a technology in which, from, for example, a list of coordinates of data processing devices serving as candidates for read destinations or write destinations of distributed data, a data processing device to serve as a read destination or a write destination is determined based on distances between coordinates of the candidates and a device itself. In addition, there is known a technology in which a set of, for example, keys is divided into segments, thereby managing, in units of segments, pieces of data memorized while being associated with the keys. In addition, there is known a technology in which files are managed by using, for example, a load information table for measuring and managing a load status of each of file servers and a file attribute table for recording and managing a file server in charge of access to each of file blocks.
As examples of the related art, Japanese Laid-open Patent Publication No. 6-332782, International Publication Pamphlet No. WO 2012/164735, and Japanese Laid-open Patent Publication No. 2010-74604 are known.